FieldItemInterface

class \Drupal\Core\Field\FieldItemBase extends \Drupal\Core\Field\FieldItemInterface implements \Drupal\Core\TypedData\Plugin\DataType\Map
class \Drupal\Core\Field\Plugin\Field\FieldType\BooleanItem extends \Drupal\Core\TypedData\OptionsProviderInterface implements \Drupal\Core\Field\FieldItemBase
class \Drupal\Core\Field\Plugin\Field\FieldType\ChangedItem implements \Drupal\Core\Field\Plugin\Field\FieldType\CreatedItem
class \Drupal\Core\Field\Plugin\Field\FieldType\CreatedItem implements \Drupal\Core\Field\Plugin\Field\FieldType\TimestampItem
class \Drupal\Core\Field\Plugin\Field\FieldType\DecimalItem implements \Drupal\Core\Field\Plugin\Field\FieldType\NumericItemBase
class \Drupal\Core\Field\Plugin\Field\FieldType\EmailItem implements \Drupal\Core\Field\FieldItemBase
class \Drupal\Core\Field\Plugin\Field\FieldType\EntityReferenceItem extends \Drupal\Core\TypedData\OptionsProviderInterface, \Drupal\Core\Field\PreconfiguredFieldUiOptionsInterface implements \Drupal\Core\Field\FieldItemBase
class \Drupal\Core\Field\Plugin\Field\FieldType\FloatItem implements \Drupal\Core\Field\Plugin\Field\FieldType\NumericItemBase
class \Drupal\Core\Field\Plugin\Field\FieldType\IntegerItem implements \Drupal\Core\Field\Plugin\Field\FieldType\NumericItemBase
class \Drupal\Core\Field\Plugin\Field\FieldType\LanguageItem extends \Drupal\Core\TypedData\OptionsProviderInterface implements \Drupal\Core\Field\FieldItemBase
class \Drupal\Core\Field\Plugin\Field\FieldType\MapItem implements \Drupal\Core\Field\FieldItemBase
class \Drupal\Core\Field\Plugin\Field\FieldType\NumericItemBase implements \Drupal\Core\Field\FieldItemBase
class \Drupal\Core\Field\Plugin\Field\FieldType\PasswordItem implements \Drupal\Core\Field\Plugin\Field\FieldType\StringItem
class \Drupal\Core\Field\Plugin\Field\FieldType\StringItem implements \Drupal\Core\Field\Plugin\Field\FieldType\StringItemBase
class \Drupal\Core\Field\Plugin\Field\FieldType\StringItemBase implements \Drupal\Core\Field\FieldItemBase
class \Drupal\Core\Field\Plugin\Field\FieldType\StringLongItem implements \Drupal\Core\Field\Plugin\Field\FieldType\StringItemBase
class \Drupal\Core\Field\Plugin\Field\FieldType\TimestampItem implements \Drupal\Core\Field\FieldItemBase
class \Drupal\Core\Field\Plugin\Field\FieldType\UriItem implements \Drupal\Core\Field\Plugin\Field\FieldType\StringItem
class \Drupal\Core\Field\Plugin\Field\FieldType\UuidItem implements \Drupal\Core\Field\Plugin\Field\FieldType\StringItem
class \Drupal\comment\Plugin\Field\FieldType\CommentItem extends \Drupal\comment\Plugin\Field\FieldType\CommentItemInterface implements \Drupal\Core\Field\FieldItemBase
class \Drupal\datetime\Plugin\Field\FieldType\DateTimeItem extends \Drupal\datetime\Plugin\Field\FieldType\DateTimeItemInterface implements \Drupal\Core\Field\FieldItemBase
class \Drupal\datetime_range\Plugin\Field\FieldType\DateRangeItem implements \Drupal\datetime\Plugin\Field\FieldType\DateTimeItem
class \Drupal\editor_test\Plugin\Field\FieldType\EditorTestTextLongItem implements \Drupal\text\Plugin\Field\FieldType\TextLongItem
class \Drupal\entity_test\Plugin\Field\FieldType\AutoIncrementingTestItem implements \Drupal\Core\Field\Plugin\Field\FieldType\IntegerItem
class \Drupal\entity_test\Plugin\Field\FieldType\ChangedTestItem implements \Drupal\Core\Field\Plugin\Field\FieldType\ChangedItem
class \Drupal\entity_test\Plugin\Field\FieldType\ComputedTestCacheableStringItem implements \Drupal\Core\Field\Plugin\Field\FieldType\StringItem
class \Drupal\entity_test\Plugin\Field\FieldType\FieldTestItem implements \Drupal\Core\Field\FieldItemBase
class \Drupal\entity_test\Plugin\Field\FieldType\InternalPropertyTestFieldItem implements \Drupal\Core\Field\Plugin\Field\FieldType\StringItem
class \Drupal\entity_test\Plugin\Field\FieldType\SerializedItem implements \Drupal\Core\Field\FieldItemBase
class \Drupal\entity_test\Plugin\Field\FieldType\SerializedPropertyItem implements \Drupal\Core\Field\FieldItemBase
class \Drupal\entity_test\Plugin\Field\FieldType\ShapeItem implements \Drupal\Core\Field\FieldItemBase
class \Drupal\entity_test\Plugin\Field\FieldType\ShapeItemRequired implements \Drupal\entity_test\Plugin\Field\FieldType\ShapeItem
class \Drupal\entity_test\Plugin\Field\FieldType\SingleInternalPropertyTestFieldItem implements \Drupal\Core\Field\Plugin\Field\FieldType\StringItem
class \Drupal\entity_test_update\Plugin\Field\FieldType\MultiValueTestItem implements \Drupal\Core\Field\FieldItemBase
class \Drupal\field_example\Plugin\Field\FieldType\RgbItem implements \Drupal\Core\Field\FieldItemBase
class \Drupal\field_permission_example\Plugin\Field\FieldType\FieldNote implements \Drupal\Core\Field\FieldItemBase
class \Drupal\field_test\Plugin\Field\FieldType\HiddenTestItem implements \Drupal\field_test\Plugin\Field\FieldType\TestItem
class \Drupal\field_test\Plugin\Field\FieldType\TestItem implements \Drupal\Core\Field\FieldItemBase
class \Drupal\field_test\Plugin\Field\FieldType\TestItemWithDependencies implements \Drupal\field_test\Plugin\Field\FieldType\TestItem
class \Drupal\field_test\Plugin\Field\FieldType\TestItemWithPreconfiguredOptions extends \Drupal\Core\Field\PreconfiguredFieldUiOptionsInterface implements \Drupal\field_test\Plugin\Field\FieldType\TestItem
class \Drupal\field_test\Plugin\Field\FieldType\TestObjectItem implements \Drupal\Core\Field\FieldItemBase
class \Drupal\file\Plugin\Field\FieldType\FileItem implements \Drupal\Core\Field\Plugin\Field\FieldType\EntityReferenceItem
class \Drupal\file\Plugin\Field\FieldType\FileUriItem implements \Drupal\Core\Field\Plugin\Field\FieldType\UriItem
class \Drupal\image\Plugin\Field\FieldType\ImageItem implements \Drupal\file\Plugin\Field\FieldType\FileItem
class \Drupal\image_module_test\Plugin\Field\FieldType\DummyAjaxItem implements \Drupal\Core\Field\FieldItemBase
class \Drupal\language\DefaultLanguageItem implements \Drupal\Core\Field\Plugin\Field\FieldType\LanguageItem
class \Drupal\layout_builder\Plugin\Field\FieldType\LayoutSectionItem implements \Drupal\Core\Field\FieldItemBase
class \Drupal\link\Plugin\Field\FieldType\LinkItem extends \Drupal\link\LinkItemInterface implements \Drupal\Core\Field\FieldItemBase
class \Drupal\media_library_test\Plugin\Field\FieldType\EntityReferenceItemSubclass implements \Drupal\Core\Field\Plugin\Field\FieldType\EntityReferenceItem
class \Drupal\options\Plugin\Field\FieldType\ListFloatItem implements \Drupal\options\Plugin\Field\FieldType\ListItemBase
class \Drupal\options\Plugin\Field\FieldType\ListIntegerItem implements \Drupal\options\Plugin\Field\FieldType\ListItemBase
class \Drupal\options\Plugin\Field\FieldType\ListItemBase extends \Drupal\Core\TypedData\OptionsProviderInterface implements \Drupal\Core\Field\FieldItemBase
class \Drupal\options\Plugin\Field\FieldType\ListStringItem implements \Drupal\options\Plugin\Field\FieldType\ListItemBase
class \Drupal\path\Plugin\Field\FieldType\PathItem implements \Drupal\Core\Field\FieldItemBase
class \Drupal\telephone\Plugin\Field\FieldType\TelephoneItem implements \Drupal\Core\Field\FieldItemBase
class \Drupal\text\Plugin\Field\FieldType\TextItem implements \Drupal\text\Plugin\Field\FieldType\TextItemBase
class \Drupal\text\Plugin\Field\FieldType\TextItemBase implements \Drupal\Core\Field\FieldItemBase
class \Drupal\text\Plugin\Field\FieldType\TextLongItem implements \Drupal\text\Plugin\Field\FieldType\TextItemBase
class \Drupal\text\Plugin\Field\FieldType\TextWithSummaryItem implements \Drupal\text\Plugin\Field\FieldType\TextItemBase
class \Drupal\user\StatusItem implements \Drupal\Core\Field\Plugin\Field\FieldType\BooleanItem
class \Drupal\user\TimeZoneItem implements \Drupal\Core\Field\Plugin\Field\FieldType\StringItem
class \Drupal\user\UserNameItem implements \Drupal\Core\Field\Plugin\Field\FieldType\StringItem

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